Types of Data Update with PSA

Prerequisites

You have defined the PSA transfer method in the transfer rules maintenance.

Features

Processing options for the PSA transfer method

In contrast to a data request with IDocs, a data request in the PSA also gives you various options for a further update of the data in the data targets. Upon selection, you need to weigh data security against performance for the loading process.

If you create an InfoPackage in the BW Scheduler, determine the type of data update on the Processing tab page.

The following processing options are available in the PSA transfer method:

Processing Option	Description	More Information
PSA and Data Targets/InfoObjects in Parallel (By Package)	A process is started to write the data from this data package into the PSA for each data package. If the data is successfully updated in the PSA, a second parallel process is started. In this process, the transfer rules are used for the package data records, data is adopted by the communication structure, and it is finally written to the data targets. Posting of the data occurs in parallel by package. This method is used to update data into the PSA and the data targets with a high level of performance. The BW system receives the data from the source system, writes it to the PSA, and starts the update immediately and in parallel into the corresponding data target.	The maximum number of processes, which is set in the source system inMaintaining Control Parameters for Data Transfer, does not restrict the number of processes in BW. Therefore, many dialog processes in the BW system could be necessary for the loading process. Make sure that enough dialog processes are available in the BW system. If the data package contains incorrect data records, you have several options allowing you to continue working with the records in the request. You can specify how the system should react to incorrect data records. More information: Handling Data Records with Errors. You also have the option of correcting data in the PSA and updating it from here (refer toChecking and Changing Data). Note the following when using transfer and update routines: If you choose this processing option and then request processing takes place in parallel during loading, the global data is deleted because a new process is used for every data package in further processing.
PSA and then to Data Target/InfoObject (by Package)	A process that writes the package to the PSA table is started for each data package. When the data has been successfully updated to the PSA, the same process writes the data to the data targets. The data is posted in serial by package. Compared with the first processing option, you have better control over the whole data flow with a serial update of data in packages, because the BW system carries it out using only one process for each data package. Only a certain number of processes are necessary for each data request in the BW system. This number is defined in the settings made in the maintenance of the control parameters in customizing for extractors.	If the data package contains incorrect data records, you have several options allowing you to continue working with the records in the request. More information:Handling Data Records with Errors. You also have the option of correcting data in the PSA and updating it from here (refer toChecking and Changing Data). Note the following when using transfer and update routines: If you choose this processing option and then request processing takes place in parallel during loading, the global data is deleted because a new process is used for every data package in further processing.
Only PSA	Using this method, data is written to the PSA and is not updated any further. You have the advantage of having data stored safely in BW and having the PSA, which is ideal as a persistent incoming data store for mass data as well. The setting for the maximum number of processes in the source system can also have a positive impact on the number of processes in BW. To further update the data automatically in the corresponding data target, wait until all the data packages have arrived and have been successfully updated in the PSA, and select Update in DataTarget from the Processing tab page when you schedule the InfoPackage in the Scheduler. A process that writes the package to the PSA table is started for each data package. If you then trigger further processing and the data is updated to the data targets, a process is started for the request that writes the data packages to the data targets one after the other. Posting of the data occurs in serial by request.	When using the InfoPackage in a process chain, this setting is hidden in the scheduler. This is because the setting is represented by its own process type in process chain maintenance and is maintained there. Handling Duplicate Data Records (only possible with the processing type Only PSA): The system indicates when master data or text DataSources transfer potential duplicate data records for a key into the BW system. The Ignore Duplicate Data Records indicator is also set by default in this case. In BW, the last data record of a request is updated for a particular key by default when data records are transferred more than once. Any other data records in the request with the same key are ignored. If the Ignore Duplicate Data Records indicator is not set, duplicate data records will cause an error. The error message is displayed in the monitor. Note the following when using transfer and update routines: If you choose this processing option and request processing takes place serially during loading, the global data is kept as long as the process with which the data is processed is in existence.

Processing Option

Description

More Information

PSA and Data Targets/InfoObjects in Parallel (By Package)

A process is started to write the data from this data package into the PSA for each data package. If the data is successfully updated in the PSA, a second parallel process is started. In this process, the transfer rules are used for the package data records, data is adopted by the communication structure, and it is finally written to the data targets. Posting of the data occurs in parallel by package.

This method is used to update data into the PSA and the data targets with a high level of performance. The BW system receives the data from the source system, writes it to the PSA, and starts the update immediately and in parallel into the corresponding data target.

The maximum number of processes, which is set in the source system inMaintaining Control Parameters for Data Transfer, does not restrict the number of processes in BW. Therefore, many dialog processes in the BW system could be necessary for the loading process. Make sure that enough dialog processes are available in the BW system.

If the data package contains incorrect data records, you have several options allowing you to continue working with the records in the request. You can specify how the system should react to incorrect data records. More information: Handling Data Records with Errors.

You also have the option of correcting data in the PSA and updating it from here (refer toChecking and Changing Data).

Note the following when using transfer and update routines:

If you choose this processing option and then request processing takes place in parallel during loading, the global data is deleted because a new process is used for every data package in further processing.

PSA and then to Data Target/InfoObject (by Package)

A process that writes the package to the PSA table is started for each data package. When the data has been successfully updated to the PSA, the same process writes the data to the data targets. The data is posted in serial by package.

Compared with the first processing option, you have better control over the whole data flow with a serial update of data in packages, because the BW system carries it out using only one process for each data package. Only a certain number of processes are necessary for each data request in the BW system. This number is defined in the settings made in the maintenance of the control parameters in customizing for extractors.

If the data package contains incorrect data records, you have several options allowing you to continue working with the records in the request. More information:Handling Data Records with Errors.

You also have the option of correcting data in the PSA and updating it from here (refer toChecking and Changing Data).

Note the following when using transfer and update routines:

Only PSA

Using this method, data is written to the PSA and is not updated any further.

You have the advantage of having data stored safely in BW and having the PSA, which is ideal as a persistent incoming data store for mass data as well. The setting for the maximum number of processes in the source system can also have a positive impact on the number of processes in BW.

To further update the data automatically in the corresponding data target, wait until all the data packages have arrived and have been successfully updated in the PSA, and select Update in DataTarget from the Processing tab page when you schedule the InfoPackage in the Scheduler.

A process that writes the package to the PSA table is started for each data package. If you then trigger further processing and the data is updated to the data targets, a process is started for the request that writes the data packages to the data targets one after the other. Posting of the data occurs in serial by request.

When using the InfoPackage in a process chain, this setting is hidden in the scheduler. This is because the setting is represented by its own process type in process chain maintenance and is maintained there.

Handling Duplicate Data Records (only possible with the processing type Only PSA):

The system indicates when master data or text DataSources transfer potential duplicate data records for a key into the BW system. The Ignore Duplicate Data Records indicator is also set by default in this case. In BW, the last data record of a request is updated for a particular key by default when data records are transferred more than once. Any other data records in the request with the same key are ignored. If the Ignore Duplicate Data Records indicator is not set, duplicate data records will cause an error. The error message is displayed in the monitor.

Note the following when using transfer and update routines:

If you choose this processing option and request processing takes place serially during loading, the global data is kept as long as the process with which the data is processed is in existence.

Further updating from the PSA

Several options are available to update the data from the PSA into the data targets.

To immediately update the request data in the background, select the request in the PSA tree and choose Context Menu (Right Mouse Button) → Start Update Immediately.
To schedule a request update using the Scheduler, select the request in the PSA tree and choose Context Menu (Right Mouse Button) → Schedule Update.
The Scheduler (PSA Subsequent Update) appears. Here you can define the scheduling options for background processing. For data with flexible update, you can also specify and select update parameters where data needs to be updated.
To further update the data automatically in the corresponding data target, wait until all the data packages have arrived and have been successfully updated in the PSA, and select Update in DataTarget from the Processing tab page when you schedule the InfoPackage in the Scheduler.
Note

When using the InfoPackage in aprocess chain, this setting is hidden in the scheduler. This is because the setting is represented by its own process type in process chain maintenance and is maintained there.

Simulating/canceling update from PSA

To simulate the data update for a request using the Monitor, select the request in the PSA tree, and choose Context menu (right mouse button) → Simulate/Cancel update.

The monitor detail screen appears. On the Detail tab page, select one or more data packages and choose Simulate Update. In the following screen, define the simulation selections and select Execute Simulation. Enter the data records for which you want to simulate the update and choose Continue. You see the data in the communication structure format. In the case of data with flexible updating, you can change to the view for data target data records. In the data target screen you can display the records belonging to the communication structure for selected records in a second window. If you have activated debugging, the ABAP Debugger appears and you can execute the error analysis there.

More information:Update Simulation in the Extraction Monitor

Processing several PSA requests at once

To process several PSA requests at once, select the PSA in the PSA tree and choose Context Menu (Right Mouse Button) → Process Several Requests. You have the option of starting the update for the selected requests immediately or using the scheduler to schedule them. The individual requests are scheduled one after the other in the scheduler. You can delete the selected requests collectively using this function. You can also call detailed information, the monitor, or the content display for the corresponding data target.

Note

During processing, a background process is started for every request. Make sure that there are enough background processes available.